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The template for rimless eyeglasses date back to the 1820s, when an Austrian inventor named Johann Friedrich Voigtländer [] marketed a rimless monocle. [2] The design as it is known today arose in the 1880s [3] as a means to alleviate the combined weight of metal frames with heavy glass lenses.
Hyper-radial or hyperradiant Fresnel lenses are Fresnel lenses used in lighthouses. They are larger than "first-order" lenses , having a focal length (radius) of 1330 mm (52.36 inches). The idea was mentioned by Thomas Stevenson in 1869 [ 1 ] and first proposed by John Richardson Wigham in 1872, and again proposed by Thomas Stevenson in 1885 ...
A Fresnel lens (/ ˈ f r eɪ n ɛ l,-n əl / FRAY-nel, -nəl; / ˈ f r ɛ n ɛ l,-əl / FREN-el, -əl; or / f r eɪ ˈ n ɛ l / fray-NEL [1]) is a type of composite compact lens which reduces the amount of material required compared to a conventional lens by dividing the lens into a set of concentric annular sections.
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The prototype, created in 1936 and known as "Anti-Glare", had plastic frames and green lenses that could cut out the glare without obscuring vision. The name "Ray-Ban" was hence derived from the ability of these glasses to limit the ingress of either ultra-violet or infra-red rays of light. [7] Impact-resistant lenses were added in 1938. [8]
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